I need to figure out how the climate of my region changed over the past 4.6 billion years, but I'm thinking if I just explain North America that would be adequate. The problem is, I can only find things on a global scale. I know that when there's glaciation, it's obviously cold, but I'm looking for a description of each period/era. Right now, it's cold at the poles and tropical at the equator. The climate isn't the same for the entire planet. I need something specific to North America.
If you could direct me as to where to look, that would be great. Thanks!
If you could direct me as to where to look, that would be great. Thanks!
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Well, that is very difficult. Climate is what happens on a global scale, really. Yes, it's warm at the tropics and cold at the poles, and that's why the rock record is important, because we can see the sequences of events as recorded in stone.
During most of the Earth's history global temperatures were probably 8 to 15 degrees Celsius warmer than today. In the last billion years of climatic history, warmer conditions were broken by glacial periods starting at 925, 800, 680, 450, 330, and 2 million years before present.
The Pleistocene Glaciation (the "Ice Age") took place from 2 million to about 14,000 years before now, and North America (along with Europe and Asian) was covered by miles-thick glaciers almost as far south as Atlanta, Georgia. Since then, the glaciers have been retreating, and we're technically just in an interglacial period (literally, between glaciers).
The first link below has detailed information for this period, including minor ice ages and warmer periods.
The second link has animations of how the plates and continents have drifted over geologic time; you can watch that and surmise things such as... when they were at the equator, they were warmer than when they were at the poles, though the entire planet might be much colder or much warmer at any give time.
The third link matches geologic time with life. You can look at what kind of life existed at a given time, and if you know if that life existed in North America, you can put together the climate.
Sorry that there isn't a better, more detailed record, but basically the entire planet "pumps" from really cold to really warm and back again as it tries to come to an equilibrium with the heat at its core.
During most of the Earth's history global temperatures were probably 8 to 15 degrees Celsius warmer than today. In the last billion years of climatic history, warmer conditions were broken by glacial periods starting at 925, 800, 680, 450, 330, and 2 million years before present.
The Pleistocene Glaciation (the "Ice Age") took place from 2 million to about 14,000 years before now, and North America (along with Europe and Asian) was covered by miles-thick glaciers almost as far south as Atlanta, Georgia. Since then, the glaciers have been retreating, and we're technically just in an interglacial period (literally, between glaciers).
The first link below has detailed information for this period, including minor ice ages and warmer periods.
The second link has animations of how the plates and continents have drifted over geologic time; you can watch that and surmise things such as... when they were at the equator, they were warmer than when they were at the poles, though the entire planet might be much colder or much warmer at any give time.
The third link matches geologic time with life. You can look at what kind of life existed at a given time, and if you know if that life existed in North America, you can put together the climate.
Sorry that there isn't a better, more detailed record, but basically the entire planet "pumps" from really cold to really warm and back again as it tries to come to an equilibrium with the heat at its core.